Global Patent Index - EP 0271284 A2

EP 0271284 A2 19880615 - Stimulation of earth formations surrounding a deviated wellbore by sequential hydraulic fracturing.

Title (en)

Stimulation of earth formations surrounding a deviated wellbore by sequential hydraulic fracturing.

Title (de)

Verfahren zur Anregung der ein abgelenktes Bohrloch umgebenden Erdformation durch sequenz-hydraulische Spaltenbildung.

Title (fr)

Procédé de stimulation d'une formation terrestre entourant un puits dévié par fracturation hydraulique séquentielle.

Publication

EP 0271284 A2 19880615 (EN)

Application

EP 87310637 A 19871203

Priority

US 93889186 A 19861208

Abstract (en)

A subsurface formation surrounding a deviated borehole and having original in-situ stresses that favor the propagation of a vertical fracture is penetrated by a cased borehole. The casing is perforated at a pair of spaced-apart intervals to form a pair of sets of perforations. Fracturing fluid is initially pumped down said cased borehole and out one of said sets of perforations to form a first fracture that is oriented in a direction perpendicular to the direction of the least principal in-situ horizontal stress. The propagation of this first vertical fracture changes the in-situ stresses so as to favor the propagation of a second vertical fracture. This is oriented in a direction parallel to the direction of the least principal in-situ horizontal stress. Thereafter, while maintaining pressure in the first vertical fracture, fracturing fluid is pumped down said cased borehole and out of the other of said sets of perforations to form such a second vertical fracture which will now link naturally occurring fractures in the formation to the deviated wellbore.

IPC 1-7

E21B 43/26

IPC 8 full level

E21B 43/26 (2006.01); E21B 43/30 (2006.01)

CPC (source: EP US)

E21B 43/26 (2013.01 - EP US); E21B 43/305 (2013.01 - EP US)

Designated contracting state (EPC)

AT DE FR GB NL

DOCDB simple family (publication)

EP 0271284 A2 19880615; EP 0271284 A3 19890503; EP 0271284 B1 19920513; AT E76159 T1 19920515; CA 1267361 A 19900403; DE 3779069 D1 19920617; US 4687061 A 19870818

DOCDB simple family (application)

EP 87310637 A 19871203; AT 87310637 T 19871203; CA 544520 A 19870814; DE 3779069 T 19871203; US 93889186 A 19861208